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diff --git a/static/freebsd/man4/lm75.4 3.html b/static/freebsd/man4/lm75.4 3.html new file mode 100644 index 00000000..3c1d4c1d --- /dev/null +++ b/static/freebsd/man4/lm75.4 3.html @@ -0,0 +1,144 @@ +<table class="head"> + <tr> + <td class="head-ltitle">LM75(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">LM75(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">lm75</code> — <span class="Nd">lm75 i2c + digital temperature sensor driver</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="Cd">device iic</code> + <br/> + <code class="Cd">device iicbus</code> + <br/> + <code class="Cd">device lm75</code></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The <code class="Nm">lm75</code> driver provides access to sensor + data and configuration over the <a class="Xr">iicbus(4)</a>.</p> +<p class="Pp">It provides an easy and simple way to check the functionality of + an i2c bus as it provides read and write access to the + <code class="Nm">lm75</code> configuration register.</p> +<p class="Pp">The access to <code class="Nm">lm75</code> data is made via the + <a class="Xr">sysctl(8)</a> interface:</p> +<div class="Bd Pp Li"> +<pre>dev.lm75.0.%desc: LM75 temperature sensor +dev.lm75.0.%driver: lm75 +dev.lm75.0.%location: addr=0x49 +dev.lm75.0.%pnpinfo: name=lm750 compat=national,lm75 +dev.lm75.0.%parent: iicbus3 +dev.lm75.0.temperature: 27.1C +dev.lm75.0.thyst: 75.0C +dev.lm75.0.tos: 80.0C +dev.lm75.0.faults: 1 +dev.lm75.0.mode: comparator +dev.lm75.0.polarity: active-low +dev.lm75.0.shutdown: 0</pre> +</div> +<dl class="Bl-tag"> + <dt id="dev.lm75._d.temperature"><var class="Va">dev.lm75.%d.temperature</var></dt> + <dd>Is the read-only value of the current temperature read by the sensor.</dd> + <dt id="dev.lm75._d.thyst"><var class="Va">dev.lm75.%d.thyst</var></dt> + <dd>Sets the hysteresis temperature. Once the temperature gets over the + overtemperature shutdown value (tos) it needs to drop below the hysteresis + temperature to disable the output (interrupt) pin again.</dd> + <dt id="dev.lm75._d.tos"><var class="Va">dev.lm75.%d.tos</var></dt> + <dd>Sets the overtemperature shutdown value. Once the temperature gets over + this value the output pin will be enabled. The way the output (interrupt) + pin works, depends on the mode configuration.</dd> + <dt id="dev.lm75._d.faults"><var class="Va">dev.lm75.%d.faults</var></dt> + <dd>Is the number of faults that must occur consecutively to activate the + interrupt (output) pin. It can be set to 1, 2, 4, and 6.</dd> + <dt id="dev.lm75._d.mode"><var class="Va">dev.lm75.%d.mode</var></dt> + <dd>Sets the operation mode for the sensor interrupt pin. It can be set to + 'comparator' (default) or 'interrupt'.</dd> + <dt id="dev.lm75._d.polarity"><var class="Va">dev.lm75.%d.polarity</var></dt> + <dd>Sets the polarity of the sensor interrupt pin. It can be set to + 'active-low' (default) or 'active-high'. Please note that the output pin + is an open-drain output and it needs a proper pull-up resistor to + work.</dd> + <dt id="dev.lm75._d.shutdown"><var class="Va">dev.lm75.%d.shutdown</var></dt> + <dd>When set to '1' it shuts down the sensor. The temperature conversion stops + but the sensor remains with its i2c bus active, i.e., it can be woken up + by setting this option to '0' again.</dd> +</dl> +<p class="Pp">Please check the <code class="Nm">lm75</code> datasheet for more + details.</p> +<p class="Pp">When used together with <a class="Xr">snmp_lm75(3)</a> it allows + the monitoring of <code class="Nm">lm75</code> temperature data over + SNMP.</p> +<p class="Pp">The <code class="Nm">lm75</code> driver supports both the low and + the high resolution models.</p> +<p class="Pp">The low resolution model (lm75) provides a 9 bit output with the + LSB representing 0.5C.</p> +<p class="Pp">The high resolution model (lm75a) provides an 11 bit output with + the LSB representing 0.125C.</p> +<p class="Pp">The driver tries to auto-detect the <code class="Nm">lm75</code> + model, but the detection of some <code class="Nm">lm75</code> clones may not + work reliably.</p> +<p class="Pp">On a <a class="Xr">device.hints(5)</a> based system, such as + <code class="Li">MIPS</code>, these values are configurable for + <code class="Nm">lm75</code>:</p> +<dl class="Bl-tag"> + <dt id="hint.lm75._d.at"><var class="Va">hint.lm75.%d.at</var></dt> + <dd>Is the <a class="Xr">iicbus(4)</a> you are attaching to.</dd> + <dt id="hint.lm75._d.addr"><var class="Va">hint.lm75.%d.addr</var></dt> + <dd>Is the <code class="Nm">lm75</code> i2c address on the + <a class="Xr">iicbus(4)</a>.</dd> +</dl> +<p class="Pp">On a <a class="Xr">FDT(4)</a> based system, such as + <code class="Li">ARM</code>, the DTS part for a <code class="Nm">lm75</code> + device usually looks like:</p> +<div class="Bd Pp Li"> +<pre>i2c { + /* Properties describing the controller appear here. */ + ... + lm750@49 { + compatible = "national,lm75"; + reg = <0x49>; + }; +};</pre> +</div> +<p class="Pp">Where:</p> +<dl class="Bl-tag"> + <dt id="compatible"><var class="Va">compatible</var></dt> + <dd>Should always be set to "national,lm75".</dd> + <dt id="reg"><var class="Va">reg</var></dt> + <dd>Indicates which 7-bit i2c address the <code class="Nm">lm75</code> is + wired at. <code class="Nm">lm75</code> temperature sensors can be wired to + 8 different addresses, allowing up to 8 sensors on the same + <a class="Xr">iicbus(4)</a>.</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">snmp_lm75(3)</a>, <a class="Xr">fdt(4)</a>, + <a class="Xr">iic(4)</a>, <a class="Xr">iicbus(4)</a>, + <a class="Xr">sysctl(8)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">lm75</code> driver first appeared in + <span class="Ux">FreeBSD 11.0</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> +<p class="Pp">The <code class="Nm">lm75</code> driver and this manual page were + written by <span class="An">Luiz Otavio O Souza</span> + <<a class="Mt" href="mailto:loos@FreeBSD.org">loos@FreeBSD.org</a>>.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">December 26, 2017</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |